This invention relates in general to radiation therapy and in particular to apparatuses and methods for providing brachytherapy to a human or other mammalian body.
Brachytherapy is a type of radiation therapy that involves placing radioactive materials directly into or immediately adjacent to a target, which may be a tumor or tissue surrounding a cavity that contains cancerous cells. Brachytherapy has been used in treatment of a large number of malignancies including cancer in the uterus, uterine cervix, vagina, prostate, rectum, lung, and breast. One major advantage of brachytherapy is that very high doses of radiation can be delivered locally to the target in a relatively short time, while relatively low doses are delivered in the surrounding tissue. This adheres to the premise in radiation therapy that tumoricidal doses must be deposited in the tumor while sparing as much normal tissue and/or critical organs as possible. The use of brachytherapy in cancer treatment is increasing, partly due to the increasing desire for organ preservation and acceptable cosmetic results.
Significant achievements in brachytherapy have been made, however challenges remain. For example, conventional brachytherapy techniques generally lack the ability to adjust the pathways of radioactive materials in a target site, resulting in less desirable treatment dosimetry. Another issue with conventional brachytherapy techniques is that they require structures often made of metal or plastic for passing radioactive materials right next to the body tissue. The bare metal structures may cause unpleasant effect on patients, prohibits CT/MR scanning of the anatomy to be treated because of excessive artifacts, and create non-uniform dose distributions or overexposure of doses to adjacent healthy tissue.